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DECKSLAB.xls

A minor input data validation "glitch" was brought to my attention yesterday in the "DECKSLAB.xls" workbook. In the "Composite Deck"
worksheet in input cell C20, there was an incorrect cell reference in the input data validation. The spreadsheet was referencing what was an empty cell, B29, where it should have been referencing cell B30, for the deck rib height.

I have made the correction and reissued the calculation.

Alex Tomanovich, P.E.

I think i have found an error in your spreadsheet DECKSLAB.xls...

For a two span condition, the negative moment (Cell B79) that it calculates is incorrect. The equation written directly beside the cell is correct as shown, but it's like you have the wrong amplification factor in the actual calculation cell B79.

It is significantly lower than what it should be. If you compare a two span case to a 3 span, the two span should be much higher, but it is significantly lower.

Can you investigate this for me and possibly revise and repost the spreadsheet for downloading?

Thanks!

Great spreadsheet by the way!

Andy Heigley, PE

Actually, by unprotecting the sheet, i've found that in the second term of the equation (the Live Load portion) you have the load magnitude divided by 12,000 instead of 1,000.

That should fix it!

Andy:

You're absolutely right! I found the typo error right away in cell O51, and it was as you said, that I had 12,000 in the live load portion of the 2-span formula instead of 1,000, converting lbs./ft. to k/ft. Shoot, I only missed it bay a factor of 12!!!!!

Seriously, dang it, I try my hardness to be error free and strive for perfection, but that quest, as you know, can just about drive one crazy. Thanks for bringing the typo error to my attention. I suppose any astute, experienced engineer, like yourself, would/should have caught that extreme inconsistency between the calculated values for a 2-span and 3-span condition. Just goes to show you that there is no substitute for taking a minute to review the results of any software that you use to see it the results make sense.

I've corrected the typo error and updated the workbook version to v1.3. I'll try to figure out how to upload spreadsheets to this website, as John Doyle has been kind enough to spoil me by doing it for me in the past. In the event that I'm unsuccessful tonight, I'll ask John to do it for me tomorrow.

Thanks,

Alex

Hi Alex I'll update your submission with the pictures and links when I find my feet again. I have just returned from Venice to find my main pc is down. I am working from a laptop at the moment. Bear with me for a couple of days.